This invention relates to disposable absorbent articles such as disposable diapers, sanitary napkins, and the like.
Disposable diapers provide substantial advantages in convenience over diapers that have to be laundered and reused, particularly when the diapers are used away from home. In recent years, many different disposable diapers have been proposed and some have been successful in the marketplace. However, even the successful diapers are inadequate in functioning properties, and their commercial success has come because consumers have been willing to accept inadequate performance as part of the price for convenience.
One design criterion which has not heretofore been met adequately is keeping moisture away from the surface of the diaper which comes into contact with the infant's skin to thereby avoid skin irritation and infection.
Another important criterion is ready conformability to the body of the infant for maximum comfort.
In one form of prior disposable diaper, creped cellulose wadding is used as the absorbent material, covered with a permeable paper-like facing material on the side to be brought into contact with the infant's skin and covered with an impervious plastic sheet on the outside. In such a diaper, the wadding becomes more or less uniformly saturated with urine as the infant voids and thus a substantial amount of moisture is only a paper's thickness away from the infant's skin. In use, the weight of the infant presses the paper-like facing layer against the saturated wadding so that substantial amounts of moisture are expressed from the diaper and pass through the facing and into contact with the infant's skin.
Finally, both the paper-like facing material and the creped wadding of this prior art diaper are relatively stiff, making for an uncomfortable diaper, particularly when sufficient wadding is present to absorb a reasonable amount of urine.
It is also known to incorporate water-insoluble but absorbent particulate matter into the absorbent region of the disposable absorbent articles. Such particulate matter is disclosed in U.S. Pat. No. 3,669,103 to Harper et al., U.S. Pat. No. 3,670,731 to Harmon, and U.S. Pat. No. 3,783,872 to King. However, such particulate matter tends to swell and form a gelatinous layer which, while quite absorbent, tends to block liquid passage therethrough. As a result the full absorptive capacity of the absorbent article of manufacture is not utilized because the liquid to be absorbed cannot reach the absorbent material.